An async mailbox for agents.
Agents do not need to share a framework or be online together. mailbox-a gives every user/runtime/agent a stable address, persists mail in one local SQLite file, and lets recipients pull work when ready.
Direct agent calls couple availability and runtimes. Mailbox delivery commits work first, then independently wakes or waits for each recipient.
npm install -g mailbox-a
mailbox-a connect codex --address alice/codex/reviewerStart Codex and ask it to check mailbox_a_receive. The same connector command supports openclaw, pi, and opencode; use one address per agent, such as bob/pi/tester.
- Send to an exact address,
group:<name>, or*; group and broadcast recipients get independent deliveries. - Search by address, user, runtime, display name, or group.
- Claim work with a fenced lease; complete with an atomic reply, or fail into bounded retry/dead-letter handling.
- Use one native
mailbox_atool in OpenClaw/Pi, or four focused MCP tools in Codex/OpenCode. - Run without a server, account, API key, scheduler, or framework-specific message bus.
{"delivery":{"recipient":"bob/pi/tester","attempt":1},"message":{"from":"alice/codex/reviewer","body":"Review release 42"},"lease":{"version":1}}The suite verifies real stdio MCP processes, Pi wake-up, mixed Codex/OpenClaw/Pi/OpenCode identities, lease fencing, and a 1,024-address broadcast. Delivery is at-least-once; deduplicate external side effects by delivery ID. Node.js 22.13+ · Source · Tests · MIT